JP2004291278A - Color management method and system in plate-making printing system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable easy and appropriate management of printing color on an upstream step in a plate-making printing system equipped with a plurality of printing machines. <P>SOLUTION: On the basis of a same color chart data, a color chart is printed with a plurality of printing machines A, B, C. The printed color chart 401 is photo-metered with a color measuring device 110 to obtain a plurality of measured color data corresponding to the printing machines A, B, C. A profile preparing device 100a uses the measured color data to prepare a profile. That is, an average measured color data Davg is prepared through an averaging process with regard to the measured data DA, DB, DC, and then, the measured color data DA, DB, DC are displayed together with the average measured color data Davg for a worker to see these data to determine whether or not reprinting the color chart is necessary. When reprinting is decided to be necessary, a commonized profile 405 displaying the color reproducibility of the printing machines A, B, C is prepared based on the average measured color data Davg. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a color management method for managing print colors in a plate making printing system, and a method for creating a profile of a printing press used for such color management.
[0002]
[Prior art]
In the plate making process, first, using a computer called the front end, data of multiple types of parts that make up printed matter, such as characters, logos, images, pictures, illustrations, etc., are created, and such multiple types of parts The edited layout data is obtained by editing the data and laying out the data at a predetermined position. Next, the edited layout data is converted into bitmap image data representing an image to be printed by a rasterizing process. Then, a printing plate is created by the plate making apparatus using the image data in the bitmap format. Thereafter, the process proceeds to a printing process, and printing is performed by a printing machine using the printing plate, and a printed matter is output. Further, in a digital printing machine, the production of a printing plate and the printing on the printing plate are performed by one device. Therefore, when the bitmap format image data is given, the printed matter corresponding to the image data is directly output. Output from the digital printer.
[0003]
Generally, a printing press has a unique color reproducibility. Therefore, colors in a printed matter, that is, printing colors are not necessarily the same even when printing based on the same image data, and slightly differ depending on the printing press. Therefore, so-called color management for managing print colors using a profile indicating the color reproducibility of the printing press has been performed. Then, the printing machine prints a predetermined color chart, creates a profile indicating the color reproducibility of the printing machine based on the colorimetric data obtained by measuring the printing color of the color chart, and prints using the profile. A workflow for creating printed matter and plate making information while managing colors reproducible on a machine in an upstream process in plate making printing work has also been proposed.
[0004]
[Patent Document 1]
JP 2001-301124 A
[0005]
[Problems to be solved by the invention]
By the way, when a printing company owns a plurality of printing presses and the plate-making printing system includes a plurality of printing presses, the printing presses that execute printing of each job to be processed by the plate-making printing system are not actually printed. It is difficult to decide by the time it is started. That is, which printing press performs printing for each job depends on the operating status of each printing press, and it is not possible to determine in advance which printing press should execute printing. Further, if a printing machine that executes printing of each job is forcibly determined in advance, one of the printing machines will be in an idle state, and the operating rate of the entire system will decrease. As described above, in the upstream process for creating the editing layout data, etc., it is not possible to specify the printing press that performs printing corresponding to each work there, so even if a profile for each printing press is prepared, the printing color It is difficult to manage colors that can be reproduced as.
[0006]
In addition, since the color reproducibility of the printing press changes with time, depending on the state of the printing press at the time of printing the color chart, the accuracy of the profile created based on the printing may be low and the printing color may not be properly managed. is there.
[0007]
In view of the above, an object of the present invention is to provide a color management method capable of easily and appropriately managing print colors in an upstream process even in a plate making printing system including a plurality of printing presses, and a method of creating a profile therefor. I do.
[0008]
Means for Solving the Problems and Effects of the Invention
A first invention is a color management method for managing print colors in a plate making printing system including a plurality of printing machines,
A printing step of printing the color chart by the plurality of printing machines based on the same image data representing a predetermined color chart,
By measuring the print color for each of the printed matter obtained by printing the color chart, a colorimetric step of generating a plurality of colorimetric data,
An averaging step of calculating an average value of colorimetric values corresponding to each other between the plurality of colorimetric data to generate average colorimetric data composed of the average values;
A profile generation step of generating a common profile common to the plurality of printing presses as a profile indicating color reproducibility of the plurality of printing presses based on the average colorimetric data,
The common profile is used for color correction of image data to be used for printing in the plate making printing system.
[0009]
According to the first aspect, a common profile is created based on average colorimetric data obtained from a plurality of colorimetric data based on a color chart printed by a plurality of printing presses, and is used for printing in a plate making printing system. This common profile is used for color correction of image data to be used. For this reason, even in an upstream process in which editing layout data is created, color correction of image data to be used for printing is performed without deciding a printing machine to be used for printing corresponding to the work. Colors that can be reproduced as colors can be managed. As a result, a more flexible workflow can be constructed as a workflow for creating printed matter and plate making information while managing colors that can be reproduced as print colors in an upstream process.
[0010]
In a second aspect, in the first aspect,
A display step of displaying a colorimetric result indicated by the plurality of colorimetric data generated in the colorimetric step,
In the profile generation step, when the operator determines that reprinting of the color chart is unnecessary based on the color measurement result displayed in the display step, the common profile is generated based on the average color measurement data. It is characterized by being performed.
[0011]
According to the second aspect, since the colorimetric result is displayed before the common profile is created, the printing machine corresponding to the colorimetric data greatly deviating from the other colorimetric data may be used as needed. After adjusting the printing press, the color chart can be printed again to obtain new colorimetric data, thereby making it possible to create a highly accurate common profile.
[0012]
In a third aspect, in the first aspect,
In the printing step, the color chart is printed at a plurality of different times by each printing machine based on the same image data,
In the colorimetric step, the plurality of colorimetric data is generated by measuring the colors of the printed matter of the color chart printed at the plurality of different times by each printing machine.
[0013]
According to the third aspect, a plurality of colorimetric data is generated by measuring the color of a printed matter of a color chart printed at a plurality of different times by each printing machine, and is calculated from the plurality of colorimetric data. A common profile is created based on the averaged colorimetric data. For this reason, since the influence of the change over time in the color reproducibility of the printing press is offset in the common profile, it is possible to stably manage print colors without large errors.
[0014]
A fourth invention is a color management method for managing print colors in a plate making printing system using a profile indicating color reproducibility of a printing press,
A printing step of printing the color chart at a plurality of different times by the same printing machine based on the same image data representing the predetermined color chart,
A colorimetric step of generating a plurality of colorimetric data by measuring a print color for each of a plurality of prints obtained by printing the color chart,
An averaging step of calculating an average value of colorimetric values corresponding to each other between the plurality of colorimetric data to generate average colorimetric data composed of the average values;
A profile generating step of generating a profile indicating the color reproducibility of the same printing press based on the average colorimetric data,
The profile is used for color correction of image data to be used for printing in the plate making printing system.
[0015]
According to the fourth aspect, a plurality of colorimetric data is generated by measuring the color of a printed matter of a color chart printed at a plurality of different times by the same printing machine, and the plurality of colorimetric data is generated from the plurality of colorimetric data. A profile is created based on the calculated average colorimetric data. Therefore, in this profile, the influence of the change over time in the color reproducibility of the printing press is offset, and stable printing color management without a large error can be performed.
[0016]
A fifth invention is a color management system for managing print colors in a plate-making printing system including a plurality of printing machines,
A colorimeter that generates a plurality of colorimetric data by measuring a plurality of prints printed by the plurality of printers based on the same image data representing a predetermined color chart;
Averaging means for calculating average values of colorimetric values corresponding to each other between the plurality of colorimetric data, thereby generating average colorimetric data composed of the average values,
Profile generating means for generating a common profile common to a plurality of printing presses as a profile indicating color reproducibility of the plurality of printing presses based on the average colorimetric data,
The common profile is used for color correction of image data to be used for printing in the plate making printing system.
[0017]
According to a sixth aspect, in the fifth aspect,
A display unit that displays a colorimetric result indicated by the plurality of colorimetric data generated by the colorimetric unit.
[0018]
A seventh invention is a color management system for managing print colors in a prepress printing system using a profile indicating color reproducibility of a printing press,
A colorimeter that generates a plurality of colorimetric data by measuring the color of printed matter printed at a plurality of different times by the same printing machine based on the same image data representing a predetermined color chart,
Averaging means for calculating average values of colorimetric values corresponding to each other between the plurality of colorimetric data, thereby generating average colorimetric data composed of the average values,
Profile generating means for generating a profile indicating color reproducibility of the same printing press based on the average colorimetric data,
The profile is used for color correction of image data to be used for printing in the plate making printing system.
[0019]
An eighth invention is a profile creation device for creating a profile indicating color reproducibility of a printing press in a plate making printing system,
By receiving a plurality of colorimetric data for a plurality of prints printed based on the same image data representing a predetermined color chart, and calculating an average value of the corresponding colorimetric values among the plurality of colorimetric data Averaging means for generating average colorimetric data comprising the average value,
And a profile generating means for generating the profile based on the average colorimetric data.
[0020]
According to the eighth aspect, when a plurality of colorimetric data obtained by measuring a color chart printed by a plurality of printing presses is received, the color reproducibility of the plurality of printing presses is improved. A common profile is created as the profile to be indicated. Further, when a plurality of colorimetric data obtained by measuring the color charts printed at a plurality of different times on the same printing machine are received, the influence of the color reproduction of the printing machine over time is offset. The created profile is created.
[0021]
A ninth invention is a profile creation method for creating a profile indicating color reproducibility of a printing press in a plate making printing system,
By receiving a plurality of colorimetric data for a plurality of prints printed based on the same image data representing a predetermined color chart, and calculating an average value of the corresponding colorimetric values among the plurality of colorimetric data An averaging step of generating average colorimetric data composed of the average value;
Generating a profile based on the average colorimetric data.
[0022]
A tenth invention is a program for creating a profile indicating color reproducibility of a printing press in a plate making printing system,
By receiving a plurality of colorimetric data for a plurality of prints printed based on the same image data representing a predetermined color chart, and calculating an average value of the corresponding colorimetric values among the plurality of colorimetric data An averaging step of generating average colorimetric data composed of the average value;
And a profile generating step of generating the profile based on the average colorimetric data.
[0023]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
<1. First Embodiment>
<1.1 Configuration of plate making printing system>
FIG. 1 is a configuration diagram showing a stencil printing system in which a color management method according to a first embodiment of the present invention is performed. This plate-making printing system includes front-end computers 111 to 113 for editing and laying out a plurality of types of parts such as characters, logos, patterns, and illustrations constituting a printed matter, and a plate-making apparatus 221 such as a plate recorder and its controller. Computer 222, a printing machine 220 that performs printing using a printing plate manufactured by the plate making device 221, a first digital printing machine 231 and a computer 232 as a controller thereof, and a second digital printing machine 233. And a computer 234 as a controller thereof, and plate making data processing for performing a process for creating a color profile for managing printing colors and a rasterizing process (RIP) for creating data used for creating a printing plate. Device 100 and plate-making data processing device 10 And a computer (hereinafter, referred to as a “management computer”) 131, 132 for managing the progress status and delivery date of work from receiving an order to printing, and each front-end computer 111 To 113 (hereinafter collectively referred to simply as “front end”), computers 222, 232, and 234 as controllers of the plate making device 221 and the digital printing machines 231 and 233, the plate making data processing device 100, and The management computers 131 and 132 are communicably connected by a LAN (Local Area Network) 500. The number of front end computers, plate making devices, digital printing machines, and the like included in the plate making printing system is not limited to the number shown in FIG. The plate making data processing device 100 and the computers 222, 232, and 234 as controllers of the plate making device 221 and the digital printing machines 231 and 233 may not be connected by a communication path such as a LAN.
[0024]
In the plate making printing system as described above, the front end creates page data in which a print target is described in a page description language by editing and laying out the above components. This page data is transferred to the plate making data processing device 100 or one of the controllers 222, 232, 234, and the plate making data processing device 100 or any controller receiving the page data performs a rasterizing process from the page data. After that, bitmap data is created as output data. Here, when the output data is created by the plate making data processing apparatus 100, the output data is transferred to one of the controllers 222, 232, and 234, and the plate making apparatus 221 connected to the controller that has received the output data. A printing plate is manufactured by using the printing plate, and printing is performed by the printing machine 220 using the printing plate, or one of the digital printing machines 231 and 233 performs printing. When the output data is produced by any of the controllers 222, 232, and 234, a printing plate is produced by a plate making device 221 connected to the controller that produced the output data, and the printing plate is used. Printing is performed by the printing machine 220, or one of the digital printing machines 231 and 233 performs printing.
[0025]
<1.2 Configuration of plate making data processor>
As described above, the plate making data processing device 100 functions as a RIP device that performs a rasterizing process for creating bitmap data used for producing a printing plate. In addition, the plate-making data processing device 100 also functions as a profile creation device that creates a color profile used for managing print colors in the plate-making printing system. Hereinafter, the configuration of the plate making data processing apparatus 100 will be described. In the plate making and printing system shown in FIG. 1, the RIP device and the profile creation device are realized by one device 100, but these may be realized as separate devices. Further, since the rasterizing process is also performed in the controllers 222, 232, and 234 such as a printing machine, the controllers 222, 232, and 234 also function as RIP devices.
[0026]
FIG. 2 is a block diagram illustrating a hardware configuration of the plate making data processing apparatus 100. The plate-making data processing apparatus 100 is realized by using a general-purpose computer such as a personal computer. In terms of hardware, in addition to the computer main body, input devices such as a keyboard 22 and a mouse 23, and auxiliary storage A hard disk device 24 as a device and a display device 26 such as a liquid crystal display or a CRT are provided. The computer main body includes a CPU 10 as a central processing unit, a program storage / work memory 12 including a RAM (Random Access Memory) and a ROM (Read Only Memory), and input devices such as a keyboard 22 and a mouse 23. Are connected, an LAN / IF unit 15 for connecting the plate making data processing device 100 to the LAN 500, a display control unit 16 to which a display device 26 is connected, and a hard disk device 24. It comprises a disk I / O interface unit 17 and a peripheral device interface unit 18 to which the colorimeter 110 is connected. The colorimeter 110 is used to generate colorimetric data by measuring the color of the color chart 401 printed by each of the printers 220, 231, 233 based on predetermined color chart data.
[0027]
The plate making data processing device 100 functions as a RIP device that performs the above-described rasterizing process when the CPU 10 loads a predetermined program installed in the hard disk device 24 into the memory 12 and executes the program. Such a RIP device is well known, and a detailed description thereof will be omitted. Further, the plate making data processing apparatus 100 is used for managing print colors in this plate making printing system by the CPU 10 loading the profile creation program 410 installed in the hard disk drive 24 into the memory 12 and executing it. It also functions as a profile creation device that creates a color profile.
[0028]
In the present embodiment, the program for realizing the functions as the RIP device and the profile creation device is provided by a computer-readable recording medium such as a CD-ROM in which those programs are recorded. That is, the user purchases a CD-ROM as a recording medium of the program, mounts it on a CD-ROM drive (not shown), reads the programs from the CD-ROM, and installs them on the hard disk drive 24. Alternatively, a program sent via the LAN 500 may be received and installed on the hard disk device 124. Further, the above program may be installed in the hard disk device 124 before the maker ships the plate making data processing device 100.
[0029]
<1.3 Management of Print Color in Plate Making Printing System>
FIG. 3 shows the configuration of a system for managing print colors in the plate making printing system shown in FIG. 1, that is, a system for implementing the color management method according to the present embodiment (hereinafter, referred to as “color management system”). FIG. 4 is a flowchart showing a procedure of a color management method according to the present embodiment. Hereinafter, the color management in the present embodiment will be described with reference to FIGS.
[0030]
In the prepress printing system in which the color management method according to the present embodiment is implemented, three printing machines A, B, and C corresponding to the printing machines 220, 231, and 233 shown in FIG. 1 are used. The color management system according to the present embodiment manages print colors in accordance with the color reproducibility of these printing machines A, B, and C, and a profile realized by the colorimeter 110 and the plate making data processing apparatus 100. And a creation device 100a. Then, using the colorimeter 110 and the profile creation device 100a, a profile 405 for managing print colors is created as described below.
[0031]
In order to manage print colors, it is necessary to create a color profile (also simply referred to as “profile”) indicating the color reproducibility of each of the printing presses A, B, and C. For that purpose, color chart data which is image data representing a color chart in which patches of various densities for various colors are arranged is required. Therefore, in the present embodiment, first, the color chart data is created (step S12), and stored in the hard disk drive 24 as color chart data 310 for color management according to the present embodiment. The color chart data may be newly created by the plate making data processing device 100 or the like as described above. However, if the existing color chart data can be used, the color chart data is previously stored in the hard disk device 24 according to the present embodiment. May be stored as color chart data 310 for color management.
[0032]
Next, a color chart is printed under the same conditions by the printing machines A, B, and C based on the color chart data 310 (step S14). Specifically, the color chart data 310 in the hard disk drive 24 is rasterized by the plate making data processing device 100 to create output data, which is transmitted to the plate making device 221 and the digital printing machines 231 and 233 by the controllers 222 and 232. , 234 to print the color charts based on the same color chart data 310 on the printing presses A, B, and C (corresponding to the printing presses 220, 231, 233) under the same conditions. Here, the same condition means that the conditions at the time of printing in each of the printing machines A, B, and C such as the reference density, paper, ink, and the like are the same. In this way, a color chart (hereinafter, referred to as a “printed color chart” or simply a “color chart”) 401 as a printed matter based on the same color chart data 310 is output from the three printing machines A, B, and C. . In the following, when it is necessary to distinguish the color charts 401 output from the three printing presses A, B, and C, the color charts 401 output from the printing presses A, B, and C are referred to as “color charts”. Chart A "," color chart B ", and" color chart C ".
[0033]
Next, the printed color charts A, B, and C are measured by a colorimeter 110 connected to the plate making data processing apparatus 100 (profile creation apparatus 100a) (step S16). Thereby, the colorimeter 110 generates colorimetric data DA, DB, and DC as colorimetric data for the color charts A, B, and C, respectively. These colorimetric data DA, DB, and DC are temporarily stored in the hard disk device 24 of the plate making data processing device 100 (profile creating device 100a). In the following, when it is not necessary to distinguish these colorimetric data DA, DB, DC, they are denoted by reference numeral “402”.
[0034]
In the present embodiment, as shown in FIG. 3, the color chart 401 is composed of a plurality of rectangular patches arranged in a matrix, and each patch has alphabets A, B, C,. Can be specified by a combination with numbers 1, 2, 3,. In the colorimetric data 402 (DA, DB, DC), the color of each patch specified by A1, A2, ..., A7, B1, B2, ..., E7 is defined by the CIE (International Commission on Illumination). Color space (L ^* a ^* b ^* ).
[0035]
Thereafter, the plate making data processing apparatus 100 executes processing corresponding to steps S18 to S24 described below based on the above-described colorimetric data 402, so that the three printing presses A, B, and C can be used in common. The created profile (hereinafter, also referred to as “common profile”) 405 is created. This processing (hereinafter referred to as “profile creation processing”) corresponds to the execution of the profile creation program 410 by the CPU 10, and the execution of the plate making data processing apparatus 100 functions as the profile creation apparatus 100a. In the profile creation processing, the CPU 10 operates as follows.
[0036]
First, an average value of colorimetric values corresponding to each other among the colorimetric data DA, DB, and DC is calculated, and colorimetric data composed of the average values is generated as average colorimetric data Davg (step S18). Now, L indicating the colorimetric value of the patch Yj in the colorimetric data DX. ^* Value, a ^* Value, b ^* If the values are expressed as Yj_X (L), Yj_X (a), and Yj_X (b), respectively (where X = A, B, C, Y = A to E, and j = 1 to 7) ), For example, L indicating the average value for patch A1 ^* Value, a ^* Value, b ^* L, indicating the color of the patch A1 in the average colorimetric data Davg ^* The value A1_avg (L), a ^* A1_avg (a), b ^* The value A1_avg (b) is as follows.
A1_avg (L) = {A1_A (L) + A1_B (L) + A1_C (L)} / 3 (1)
A1_avg (a) = {A1_A (a) + A1_B (a) + A1_C (a)} / 3 (2)
A1_avg (b) = {A1_A (b) + A1_B (b) + A1_C (b)} / 3 (3)
Similarly, the average value of the other patches A2 to E7 is
A2_avg (L) = {A2_A (L) + A2_B (L) + A2_C (L)} / 3 (4)
A2_avg (a) = {A2_A (a) + A2_B (a) + A2_C (a)} / 3 (5)
A2_avg (b) = {A2_A (b) + A2_B (b) + A2_C (b)} / 3 (6)
・ ・ ・ ・ ・ ・ ・ ・ ・ ・
E7_avg (L) = {E7_A (L) + E7_B (L) + E7_C (L)} / 3 (7)
E7_avg (a) = {E7_A (a) + E7_B (a) + E7_C (a)} / 3 (8)
E7_avg (b) = {E7_A (b) + E7_B (b) + E7_C (b)} / 3 (9)
It becomes.
[0037]
Next, the colorimetric data DA, DB, and DC are displayed on the display device 26 together with the average colorimetric data Davg composed of the average values calculated as described above (step S20). FIG. 5 shows a display example at this time. In this example, the horizontal axis represents the arrangement of patches (density scale) in which the density changes sequentially, and the vertical axis represents the measured value indicating the density. The operator looks at this display and determines whether or not to print the color chart again. In the example shown in FIG. 5, it can be seen that the density value in the colorimetric data DC greatly deviates from the density values in the other colorimetric data DB and DA. In this display example, since the density value in the average colorimetric data Davg is also shown, it is easily recognized that, based on this, the density value in the colorimetric data DC is greatly different from the others. it can.
[0038]
In this case, the operator determines that the color chart should be printed again for the printing press C, and instructs the plate making data processing apparatus 100 and the like to perform printing of the color chart again by a predetermined operation. As a result, Yes is determined in step S22, the process returns to step S14, and the subsequent steps are repeated. In this case, instead of reprinting in all the printing machines A, B, and C, the printing machine C corresponding to the colorimetric data DA and DB or the colorimetric data that is largely deviated from the average colorimetric data Davg. It is preferable to print the color chart again only for the three color measurement data DA, DB, and DC including the new color measurement data DC. In the example shown in FIG. 5, the halftone indicated by the colorimetric data DC is swelled with respect to the colorimetric data DB and DC. In this case, the operator performs reprinting after adjusting the dot gain of the printing press C so as to lower it. By such reprinting, the colorimetric data of all the printing presses A, B, and C can be made uniform (variation between data can be reduced).
[0039]
On the other hand, the operator sees the display in step S20 and determines that there is little variation among the colorimetric data DA, DB, and DC and that reprinting of the color chart is unnecessary (No in step S22). The process proceeds to step S24 based on a predetermined operation of the operator, and the profile creation device 100a performs three printings based on the average colorimetric data Davg (step S18) created from the colorimetric data DA, DB, and DC. A common profile 405 is created for machines A, B, and C (step S24).
[0040]
As a specific method of creating a profile, various well-known methods or known methods can be employed. For example, the color chart data 310 is stored in a color space (L ^* a ^* b ^* ) And the average colorimetric data expressed in the color space (L ^* a ^* b ^* ) Is determined by the least square method or the like so that the colorimetric value Lab_avg expressed by the value in ()) is (approximately) related to the matrix M as in the following equation. be able to.
Lab = [M] Lab_avg (10)
Here, L indicating the ideal value Lab of the patch Yj (Y = A to E, j = 1 to 7) ^* Value is Yj_r (L), a ^* Value is Yj_r (a), b ^* When the value is Yj_r (b),
Lab = ^t (Yj_r (L), Yj_r (a), Yj_r (b)) (11)
(However, “t” added above the left parenthesis on the right side means transposition. The same applies hereinafter.) Also,
Lab_avg = ^t (Yj_avg (L), Yj_avg (a), Yj_avg (b)) (12)
It is.
[0041]
When the common profile 405 is created as described above, the profile creation device 100a stores the common profile 405 in the RIP device 100b (Step S26). In the present embodiment, since the profile creation device 100a and the RIP device 100b are realized by the plate making data processing device 100 which is the same device, the created common profile 405 is stored in the hard disk drive 24 of the plate making data processing device 100. Should be kept as it is. If not, the common profile 405 is transferred to the RIP device 100b via a LAN or the like.
[0042]
After that, in the RIP device 100b, when performing the rasterizing process for creating a printing plate, regardless of which printing machine A, B, or C (printing machine 220, 231, 233), the rasterizing is performed. After performing color correction on the image data before the process using the common profile 405, the rasterizing process is performed. In addition, the designer who creates the editing layout data in the upstream process uses the common profile 405 to check the colors that can be reproduced on the printing press, and to create the component data to be included in the printed matter and edit the layout. Will do.
[0043]
<1.4 Effects>
According to the above-described embodiment, even when the plate-making printing system includes a plurality of printing presses, the color correction performed before the rasterization process is used for printing in consideration of the color reproducibility of the printing press. Even if the printing machine to be executed is undetermined, it can be performed appropriately. Further, in the upstream process, it is possible to manage colors that can be reproduced as print colors without determining a printing machine on which printing corresponding to the job in progress is performed. Therefore, it is possible to construct a more flexible workflow as a workflow for creating prints and plate making information while managing colors that can be reproduced as print colors in an upstream process.
[0044]
In the above embodiment, since the colorimetric result is displayed before the common profile 405 is created (see step S20 in FIG. 4 and FIG. 5), the colorimetric result is largely different from other colorimetric data and average colorimetric data. For the printing press corresponding to the deviated colorimetric data, the color chart is printed again to newly obtain the colorimetric data, whereby a highly accurate common profile 405 can be created. Since the printing press has the instability that the printing color etc. fluctuates depending on the state, it is effective to adjust the printing press before checking the color measurement result and performing reprinting in this way. Yes, and from the display of the color measurement result, it is possible to know the contents to be adjusted in the printing press.
[0045]
<2. Second Embodiment>
In the first embodiment, the average colorimetric data obtained by averaging the colorimetric data DA, DB, and DC of the color chart printed by the plurality of printing machines A, B, and C based on the same color chart data 310 A common profile 405 to be used for print color management is created from Davg. In the color management method according to the present embodiment, instead, the color chart is printed at a plurality of different times by the same printing machine based on the same color chart data 310, and the color chart is obtained by averaging those color measurement data. From the average colorimetric data, a profile to be used for managing printing colors for the printing machine is created.
[0046]
In the present embodiment, instead of using the colorimetric data of the color chart printed by the plurality of printing presses A, B, and C as the colorimetric data DA, DB, and DC, respectively, the same printing press, for example, the printing press A, is used. Printing a color chart at a plurality of different time points, for example, a predetermined first time point, a second time point one week after the first time point, and a third time point two weeks after the first time point Then, the colorimetric data of the color chart printed at the first, second, and third time points are set as colorimetric data DA, DB, and DC, respectively. With this configuration, the average colorimetric data Davg is calculated in the same manner as described above by using the colorimetric data DA, DB, and DC, and the averaging is performed in the same manner as described above using the average colorimetric data Davg. Profile (hereinafter referred to as “average profile”). That is, the system configuration for implementing the color management method according to the present embodiment in this case is as shown in FIG.
[0047]
As described above, the printing press has the instability that the printing color and the like fluctuate depending on the state. However, according to the present embodiment, the average colorimetric data obtained by the temporal Since the average profile is created on the basis of Davg, the change over time in the color reproducibility of the printing press due to such instability is offset, and stable printing color management without a large error becomes possible. .
[0048]
<3. Third Embodiment>
In this embodiment, the averaging process for the printing press, which averages the colorimetric data of the color charts printed by the plurality of printing presses A, B, and C, as in the first embodiment, Averaging process for averaging the colorimetric data of the color chart printed at a plurality of different time points (for example, the first, second, and third time points) by each printing machine as in the embodiment of FIG. To generate average colorimetric data Davg.
[0049]
For this purpose, a plurality of colorimetric data are obtained for each printing machine by measuring the colors of the color chart printed at a plurality of different times by each printing machine. For example, by printing a color chart based on the same color chart data 310 by each of the printing presses A, B, and C at the first, second, and third time points, three printing presses A, B, and C are used. Colorimetric data is created, and a total of 3 × 3 = 9 colorimetric data DA1 to DA3, DB1 to DB3, and DC1 to DC3 are obtained. Then, average colorimetric data Davg is generated from these nine colorimetric data DA1 to DA3, DB1 to DB3, DC1 to DC3 in the same manner as in the first embodiment, and the first colorimetric data Davg is generated based on the average colorimetric data Davg. A profile to be used for print color management can be created in the same manner as in the embodiment. In other words, the system configuration for implementing the color management method according to the present embodiment in this case is as shown in FIG.
[0050]
According to the present embodiment as described above, in a plate making printing system including a plurality of printing presses, in the upstream process, not only can a flexible printing color management be performed without determining a printing press to be used for printing, but also The change over time in color reproducibility is canceled, and stable printing color management without a large error becomes possible. That is, it is possible to easily and appropriately manage print colors in an upstream process in a plate making printing system including a plurality of printing machines.
[Brief description of the drawings]
FIG. 1 is a configuration diagram illustrating a stencil printing system in which a color management method according to a first embodiment of the present invention is implemented.
FIG. 2 is a block diagram illustrating a hardware configuration of a plate-making data processing apparatus that creates a profile used for performing a color management method according to the first embodiment.
FIG. 3 is a block diagram showing a system configuration for implementing the color management method according to the first embodiment, together with other related components.
FIG. 4 is a flowchart illustrating a procedure of a color management method according to the first embodiment.
FIG. 5 is a diagram showing a display example of a color measurement result displayed in the implementation of the color management method according to the first embodiment.
FIG. 6 is a block diagram showing a system configuration for implementing a color management method according to a second embodiment of the present invention, together with other components related thereto.
FIG. 7 is a block diagram illustrating a system configuration for implementing a color management method according to a third embodiment of the present invention, together with other components related thereto.
[Explanation of symbols]
10 ... CPU
12 ... memory
26 Display device
100 ... data processing device for plate making
100a ... RIP device
100b: Profile creation device
110 ... colorimeter
310… color chart data
401… (printed) color chart
402 ... colorimetric data
403… Color measurement result display
405… (common) profile
410… Profile creation program
DA, DB, DC ... colorimetric data
Davg: Average colorimetric data

Claims (10)

A color management method for managing print colors in a plate-making printing system including a plurality of printing machines,
A printing step of printing the color chart by the plurality of printing machines based on the same image data representing a predetermined color chart,
By measuring the print color for each of the printed matter obtained by printing the color chart, a colorimetric step of generating a plurality of colorimetric data,
An averaging step of calculating an average value of colorimetric values corresponding to each other between the plurality of colorimetric data to generate average colorimetric data composed of the average values;
A profile generation step of generating a common profile common to the plurality of printing presses as a profile indicating color reproducibility of the plurality of printing presses based on the average colorimetric data,
A color management method, wherein the common profile is used for color correction of image data to be used for printing in the plate making printing system. A display step of displaying a colorimetric result indicated by the plurality of colorimetric data generated in the colorimetric step,
In the profile generation step, when the operator determines that reprinting of the color chart is unnecessary based on the color measurement result displayed in the display step, the common profile is generated based on the average color measurement data. The color management method according to claim 1, wherein the color management is performed. In the printing step, the color chart is printed at a plurality of different times by each printing machine based on the same image data,
The method according to claim 1, wherein, in the color measurement step, the plurality of color measurement data is generated by measuring a color of a printed matter of the color chart printed at the plurality of different times by each printing press. The described color management method. A color management method for managing print colors in a plate-making printing system using a profile indicating color reproducibility of a printing press,
A printing step of printing the color chart at a plurality of different times by the same printing machine based on the same image data representing the predetermined color chart,
A colorimetric step of generating a plurality of colorimetric data by measuring a print color for each of a plurality of prints obtained by printing the color chart,
An averaging step of calculating an average value of colorimetric values corresponding to each other between the plurality of colorimetric data to generate average colorimetric data composed of the average values;
A profile generating step of generating a profile indicating the color reproducibility of the same printing press based on the average colorimetric data,
A color management method, wherein the profile is used for color correction of image data to be used for printing in the plate making printing system. A color management system for managing print colors in a plate-making printing system having a plurality of printing machines,
A colorimeter that generates a plurality of colorimetric data by measuring a plurality of prints printed by the plurality of printers based on the same image data representing a predetermined color chart;
Averaging means for calculating average values of colorimetric values corresponding to each other between the plurality of colorimetric data, thereby generating average colorimetric data composed of the average values,
Profile generating means for generating a common profile common to a plurality of printing presses as a profile indicating color reproducibility of the plurality of printing presses based on the average colorimetric data,
A color management system, wherein the common profile is used for color correction of image data to be used for printing in the plate making printing system. The color management system according to claim 5, further comprising a display unit configured to display a colorimetric result indicated by the plurality of colorimetric data generated by the colorimetric unit. A color management system for managing print colors in a prepress printing system using a profile indicating color reproducibility of a printing press,
A colorimeter that generates a plurality of colorimetric data by measuring the color of printed matter printed at a plurality of different times by the same printing machine based on the same image data representing a predetermined color chart,
Averaging means for calculating average values of colorimetric values corresponding to each other between the plurality of colorimetric data, thereby generating average colorimetric data composed of the average values,
Profile generating means for generating a profile indicating color reproducibility of the same printing press based on the average colorimetric data,
A color management system, wherein the profile is used for color correction of image data to be used for printing in the plate making printing system. A profile creation device for creating a profile indicating color reproducibility of a printing press in a plate making printing system,
By receiving a plurality of colorimetric data for a plurality of prints printed based on the same image data representing a predetermined color chart, and calculating an average value of the corresponding colorimetric values among the plurality of colorimetric data Averaging means for generating average colorimetric data comprising the average value,
A profile generation unit that generates the profile based on the average colorimetric data. A profile creation method for creating a profile indicating color reproducibility of a printing machine in a plate making printing system,
By receiving a plurality of colorimetric data for a plurality of prints printed based on the same image data representing a predetermined color chart, and calculating an average value of the corresponding colorimetric values among the plurality of colorimetric data An averaging step of generating average colorimetric data composed of the average value;
A profile generating step of generating the profile based on the average colorimetric data. A program for creating a profile indicating the color reproducibility of a printing press in a plate making printing system,
By receiving a plurality of colorimetric data for a plurality of prints printed based on the same image data representing a predetermined color chart, and calculating an average value of the corresponding colorimetric values among the plurality of colorimetric data An averaging step of generating average colorimetric data composed of the average value;
A profile generating step of generating the profile based on the average colorimetric data.

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